Avian Influenza and Food Supply Safety Avian Influenza and Food Supply Safety
U.S. Food and Drug Administration
What is avian influenza?
Avian influenza (AI)–the bird flu–is a virus that infects wild birds (such as ducks, gulls, and shorebirds) and domestic poultry (such as chickens, turkeys, ducks, and geese). There is a flu for birds just as there is for humans and, as with people, some forms of the flu are worse than others.
AI strains are divided into two groups based upon the ability of the virus to produce disease in poultry: low pathogenic avian influenza (LPAI) and highly pathogenic avian influenza (HPAI).
LPAI, or “low path” avian influenza, naturally occurs in wild birds and can spread to domestic birds. In most cases it causes no signs of infection or only minor sickness in birds. These strains of the virus pose little threat to human health.
HPAI, or “high path” avian influenza, is often fatal in chickens and turkeys. HPAI spreads more rapidly than LPAI and has a higher death rate in birds. HPAI H5N1 is the type rapidly spreading in some parts of the world.
How is avian influenza spread?
AI is primarily spread by direct contact between healthy birds and infected birds, and through indirect contact with contaminated equipment and materials. The virus is excreted through the feces of infected birds and through secretions from the nose, mouth and eyes.
Contact with infected fecal material is the most common of bird-to-bird transmission. Wild ducks often introduce LPAI into domestic flocks raised on range or in open flight pens through fecal contamination. Within a poultry house, transfer of an HPAI virus between birds also can occur via airborne secretions. The spread of avian influenza between poultry premises almost always follows the movement of contaminated people and equipment.
AI also can be found on the outer surfaces of egg shells and in the case of HPAI, can infect the inside of the egg which includes the yolk and albumen or the egg white. Transfer to eggs is a potential means of AI transmission. Airborne transmission of virus from farm to farm is highly unlikely under usual circumstances.
HPAI can be spread from birds to people as a result of extensive direct contact with infected birds. Broad concerns about public health relate to the potential for the HPAI virus, such as the HPAI H5N1, to mutate, or change into a form that could spread easily from person to person. The U.S. Department of Health and Human Services is aggressively working to ensure public health is protected.
Can I get avian influenza from eating poultry or eggs?
AI is not transmissible by eating poultry or eggs that have been properly prepared. If HPAI were detected in the United States, the chance of infected poultry or eggs entering the food chain would be extremely low because of the rapid onset of symptoms in poultry as well as the safeguards in place, which include testing of flocks, and Federal inspection programs.
Hens infected with HPAI usually stop laying eggs as one of the first signs of illness, and the few eggs that are laid by infected hens generally would not get through egg washing and grading because the shells are weak and misshapen. In addition, the flow of eggs from a facility is stopped at the first suspicion of an outbreak of HPAI without waiting for a confirmed diagnosis. Therefore, eggs in the marketplace are unlikely to be contaminated with HPAI.
Cooking poultry, eggs, and other poultry products to the proper temperature and preventing cross-contamination between raw and cooked food is the key to safety. You should follow the same handling practices that are recommended to prevent illness from common foodborne pathogens such as Salmonella:
Wash hands with warm water and soap for at least 20 seconds before and after handling raw poultry and eggs.
Clean cutting boards and other utensils with soap and hot water to keep raw poultry or eggs from contaminating other foods.
Cutting boards may be sanitized by using a solution of 1 tablespoon chlorine bleach and 1 gallon of water;
Cook poultry to an internal temperature of at least 165 degrees Fahrenheit. Consumers can cook poultry to a higher temperature for personal preference.
Cook eggs until the yolks and whites are firm. Casseroles and other dishes containing eggs should be cooked to 160 degrees Fahrenheit.
Use either shell eggs that have been treated to destroy Salmonella by pasteurization or another approved method, or pasteurized egg products for recipes that call for eggs that are raw or undercooked when the dish is served. Some examples of these kinds of dishes are Caesar salad dressing and homemade ice cream. Commercial mayonnaise, dressing, and sauces contain pasteurized eggs that are safe to eat. Treated shell eggs are available from a growing number of retailers and are clearly labeled. Pasteurized egg products are widely available.